SHENANDOAH, Iowa — Fog may have diverted Sen. Hillary Rodham Clinton's plane from her campaign stop here on Tuesday, but that did not prevent her from continuing her attacks on Sen. Barack Obama's experience.

It was an odd moment. Clinton, her voice piped in over a sound system, apologized for missing the event, expressed concern about the safety of food and toys from overseas and, pivoting off the overseas topic, tweaked Obama for saying on Monday that living overseas as a child had increased his experience in foreign relations.

Clinton, who has been making an issue of Obama's experience this week in Iowa, said the next president would face two wars and fraying alliances. She said she had traveled broadly and had "met with countless world leaders" and knew many of them personally.

"Now voters will judge whether living in a foreign country at the age of 10 prepares one to face the big, complex international challenges that the next president will face," Clinton said. "I think we need a president with more experience than that."

That was apparently a response to Obama's citing his years in Indonesia as a child as contributing to his knowledge "of how ordinary people in these other countries live."

"I sit on the Senate Foreign Relations Committee," he said. "So I have frequent interaction with world leaders who come to visit here and I take trips on various fact-finding missions, whether it's to Iraq or Russia or Africa. But you know, probably, the strongest experience I have in foreign relations is the fact that I spent four years living overseas when I was a child in Southeast Asia."

Bill Burton, a spokesman for Obama, said in response to Clinton: "Dick Cheney and Don Rumsfeld have spent time in the White House and traveled to many countries, as well. But along with Hillary Clinton, they led us into the worst foreign policy disaster in a generation."

In New Hampshire, Obama presented an $18 billion education plan intended to overhaul the Bush administration's No Child Left Behind program. He said that effort was insufficiently financed and improperly carried out.

Obama outlined a proposal to make schools more accountable by stimulating learning rather than punishments for poor test scores.

Obama said the blame should not rest solely on President Bush, but also on lawmakers who did not vote to provide enough money for the program. He criticized rivals by name, Clinton and former Sen. John Edwards of North Carolina.